Compressor



June 6, 1933. F, A, WEGENER 1,912,926

COMPRESSOR Filed March 3, 1927 3 Sheets-Sheet l June 6, 1933. F. A.WEGENER COMPRESSOR Filed March 3, 1927 3 Sheets-Sheet 3 INVENTOR M 4 wPatented June 6, 1933 UNITED STATES PATENT OFFICE FRANCIS A. W'EGEN'ER,OF GLOUCESTER CITY, N EW JERSEY, ASSIGNOR TO WELSBACH COMPANY, OFGLOUCESTER CITY, NEW JERSEY, A CORPORATION OF NEW JERSEY COMPRESSORApplication filed March 3, 1927. Serial No. 172,327.

The present invention relates broadly to the art of pumps orcompressors, and more particularly to an improved compressor structurespecially adaptable for use in regfrigerating systems for effectingcompression of the refrigerant used therein. The utility of theinvention, however, is not limited with res ect to its particular use,it being equally adaptable for use in other systems wherein leakage ineither direction with respect to the compressor or system isobjectionable.

It is customary in the refrigeration art to provide systems both of theso-called flooded type and also of the so-called dry type. In all ofthese systems, however, it is necessary to utilize a compressor, and ina large number of systems it is necessary to provide control valves,these valves comprising expansion valves, check valves or the like forcontrol purposes.

Provision must be made in refrigerating systems for not only effectivelylubricating the compressor parts but also for sealing the compressoragainst leakage in either direction, leakage from the compressor to theatmosphere or in the reverse direction being objectionable. It is alsoimportant to provide means which will prevent sticking of the valves andalso prevent freezing thereof under the low temperature conditions towhich they are subjected.

I have found that very desirable results may be obtained in arefrigerating system by so constructing a compressor as to maintain, ineffect, a liquid seal effective for preventing leakage of gas past thepiston, and at the same time tending to improve the efliciency thereof.It is essential, however, in

40 well lubricated systems, to prevent undue circulation of thelubricating or sealing liquid with a refrigerant. It is one of theobjects of the present invention, therefore, to provide an improvedcompressor structure including a piston, preferably liquid sealed asreferred to, and including means for effectively separating the liquidso utilized from the refrigerant.

Another of the objects of the present invention is to provide animproved compressor structure having an effectively sealed andlubricated stuffing box, whereby leakage therethrough in eitherdirection is decreased to a minimum. The preferred structurecontemplates sealing the stuffing box by completely submergin the same,thereby precluding the possibility of gas leakage past the same. When sosealed it will be apparent that if any leakage of any character occurs,the leakage must be of the liquid utilized for sealing purposes.

Still another object of the present invention is to provide in arefrigerating system, means for effectively lubricatin the differentvalves therein and preventing f reezing thereof without possibility ofundue liquid circulation. The prevention of freezing applies to thevarious control valves throughout the system, including the expansionvalve or floor valve.

Still another object of the present invention is to provide an improvedseparator cooperating with the refrigerating medium being circulated tocontrol not only the head pressure available on the liquid for sealingpurposes, butalso for limiting the maximum amount of liquid which can becirculated.

In the accompanying drawings, I have shown for purposes of illustrationonly, certain preferred embodiments of the present invention, it beingunderstood that the drawings do not define the limits of my invention aschanges in the construction and operation disclosed therein may be madewithout de parting either from the spirit of my invention or the scopeof my broader claims.

In the drawings:

Fig. l is a diagrammatic view of a so-called dry system;

Fig. 2 is a view similar to Fig. 1 illustrating diagrammatically aso-called flooded system;

Fig. 3 is a top plan view of one form of compressor constructed inaccordance with the present invention;

Fig. 4 is a vertical sectional view on a line IV-IV of Fig. 3, thisfigure illustrating the improved separator and shut-off valve incooperative position;

Fig. 5 is an end elevation of the shut-off valve illustrating theseparator baflle and method of supporting the same.

Fig. 6 is a side elevational View illustrating the compressor shaft;

Fig. 7 is a side elevational View illustrating the compressor piston;

Fig. 8 is an end elevation of the left hand compressor head as viewed inFig. 3;

Fig. 9 is a view similar to Fig. 8 of the right hand compressor head;and,

Fi 10 is a vertical sectional view on .a line X of Fig. 9 looking in thedirection of the arrows.

Fig. 11 is a sectional view of inlet fitting 35 on line XIXI of Fig. 10.

The present invention is not limited in its application to anyparticular art or compressor details, and the accompanying drawings andspecification refer to the refrigerating art and to a particularcompressor, in many cases, merely for the purpose of a clearerunderstanding of the invention. Certain of the features are ofparticular advantage in a refrig rating system, however, as will be moreclearly apparent from the following detailed description.

In all systems of this general nature Water is present in varyingamounts. This water tends to freeze and thereby produce sticking of thevalves. sirable results can be obtained in such refrigerating systems bythe use of glycerine or a glycerine mixture as hereinafter referred to,the glyrerine serving not only to seal the system and give the desiredlubrication, but also to lower the freezing point of the water. Theglycerine or glycerine mixture is therefore effective for thawing out orpreventing freezing of the different valves with which the water comesinto contact.

Further, in accordance with the present .invention there is preferablyprovided a compressor of the pistontype having a double stroke andeffective upon movement in each direction for compressing gas in one endthereof and for drawing into the opposite end a fresh charge of gas tobe compressed.

The compressor is advantageously so constructed as to maintain at alltimes a body of sealing liquid such as glycerine, .intermediate the endsof the piston, whereby the piston is completely liquid sealed againstthe leakage of gas under pressure between the same and the cylinderwalls. It is also desirable that the pressure conditions shall be suchat all times as to tend to force the sealing liquid into the as space tothereby not only improve the efficiency of the pump, but

also to effectively lubricate the moving parts. All of the foregoinresults, together with an effective control the amount of liquid incirculation in the system are obtained b providing a compressor incombination with separating means so positioned as to effect aseparation of the refrigerant and glyeerine I have found that very deorother liquid, while maintaining such liquid in position to serve thepurposes referred to.

All of these results may be obtained in accordance with the presentinvention either with a dry system or a flooded system. Each of thesesystems, as illustrated in Figs. 1 and 2, comprises a compressor 2, acondenser 3, and a receiver 4 for the condensed refrig: erant. Thereceiver in the so called dry system has a suitable connection 5 with anexpansion valve 6 leading to the refrigerating or evaporating coils 7,while in the flooded system a similar connection 5 leads to a floatcontrolled evaporator 7. In each case, the evaporating unit has a returnconnection 8 to the intake of the compressor. It will be apparent thatin such systems, unless special means is provided for effecting aseparation of lnln'icating liquid from the gaseous refrigerating medium,such liquid would tend at all times to pass from the compressor with therefrigerant, thereby not only interfering with the desired operation ofthe parts by reason of too great an amount of liquid in the system, butalso by reason of the fact that the compressor would be robbedcorrespondingly of its lubricating and sealing material.

As illustrated in the drawings, the compressor may comprise a suitablecylinder 9, the opposite ends of which are of substantially similarconstruction except that one is necessarily reversed bodily with respectto the other. The cylinder 9 has formed in the upper wall thereof alongitudinally extending port 10 communicating at its central portionwith an outlet and collecting reservoir 11. At its opposite ends theport 10 communicates with a passage 12 in the left hand head of Fig. 8and a similar passage 13 in the right hand head of Fig. 3). Each ofthese passages communicates at its lower end with a valve chamber 14,having suitable closing means 15 for the outer end thereof. The closingmeans is preferably of such construction as to provide a projection 16adapted to cooperate with a compression spring 17 at one end and holdthe same in position. Each of these springs, at its opposite endcooperates with a similar projection 18 on a disk valve 19 having aguide stem 20 movable in a central port 21 in the head. Each disk is ofsuch diameter as to effectively cooperate with a series of outlet ports22.

The c Iinder 9 is provided with a second longitu inally extending port23 similar to the port 10 before referred to, and communicating at itsopposite ends with a passage 24in the left hand head of Fig. 8 and a passage 25 in the right hand head of Fig. 9. Each of, these passages inturn communicates with a valve chamber 26 adapted to permit the passageof a. gaseous refrigerant into the respective ends of the compressor.Each of nut.

these intake chambers 26 has a series of orts 27 communicating with theinterior 0 the cylinder, and preferably of a construction generallysimilar to that of the outlet ports 22 leading to the outlet casings 14.Each of the inlet valves may comprise a disk-like body 28 cooperatingwith the openings 27 and carried by a stem 29 extending through acentral opening 30; Each stem 29 has positioned therearound acompression spring 31 held in position by a suitable washer and cotterassembly 32 as well understood in the art, whereby the springs 31 areeffective for normally holding the valves 28 in position to seal theopenings '27.

The inlet chamber closing means 33 for one of the inlet members may betapped, as indicated for example in Fig. 10 to receive the threaded end34 of the inlet fitting 35. The opposite end of this fitting has athreaded connection 36 to cooperate with the refrigerant return line 8before referred to. This fitting is preferably formed with an axial port37 with which communicates a lateral port 38 adapted to be controlled bya valve 39. When the valve 39 is unseated it permits the refrigerant topass from the port 37 through the port 38 to a port 40. This lastmentioned port may communicate with a suitable connection 41 leading toa gauge by means of which the pressure in the return to the compressormay be determined at will.

Extending transversely through the cylinder 9 is a compressor shaft 42journaled at one end in a closed. cap 43 cooperating with the bearingextension 44. The opposite end of the shaft 42 is formed with anenlargement 45 adapted to work in a bearing 46 within an extension 47.The bearing 46 is preferably in the form of a spider providing a seriesof channels 48 communicating with the interior of the cylinder 9 at oneend and with the stufiing box chamber 49 at the opposite end. The shaft42 is provided adjacent the bearing portion 45 with a threaded portion50 adapted to receive athrust nut 51, a suitable gasket 52 preferablybeing interposed between the thrust nut 51 and the end of the bearingportion 45 to preclude possibility of leakage from the stuffing boxchamber 49 past the thrust nut and around the threaded portion. Securedat one end to the thrust nut 51, preferably in such manner as to form ahermetic seal or closure in connection therewith, is a flexible casing53, the casing preferably being soldered to the thrust t its oppositeend the casing 53 is similarly secured to a lock-nut 54 which isthreaded or otherwise secured onto a hardened steel bearing nut 55. Thebearing nut and thrust nut are urged in opposite directions by a spring56 located within the flexible casing 53. Since the thrust nut 51 isincapable of axial movement, the nut 50 is urged to the right as viewedin Fig. 4 and into engagement with a ring 57 of sealing and lubricatingmaterial, such for example as the Well known Genelite material. Thisring of lubricating material is carried in a head 57 through which theshaft 42 projects to provide a driving portion 58.

By reason of the stufling box connection just described, leakage of gasfrom the stuffing box casing 49 into the interior of the flexible casing53 is prevented at one end by the gasket 52 and at the opposite end bythe gasket 59 between the lock nut 54 and the hardened steel nut 55. Theopposite end of the casing is effectively sealed by the contact betweenthe nut 55 and the bearing ring 57. This construction, therefore, is notonly effective for preventing leakage of material from the interior ofthe stufiing box outwardly around the shaft in cases of an excesspressure within the compressor, but likewise for preventing leakage inthe opposite direction in cases of decreased pressure within thecondenser. The construction is therefore extremely desirable in casesWhere a tight joint is desired. This particular construction is made thesubject matter of my copending application Serial No. 114,466 filed June8th, 1926.

Intermediate its ends the shaft 42' is provided with a cam 60 adapted tocooperate with a cross head 61 within the piston 62 whereby uponrotation of the shaft the piston will alternately be reciprocated inalternate directions as will be understood.

On each stroke of the piston, compression will occur in one end thereofwhich compres sion will be effective for unseating one of the outletvalves 19 and forcing the compressed mixture into the correspondingpassage 12 or 13 and thence into the longitudinally extending port 10.At the same time a mixture will be drawn into the opposite end of thecylinder past one of the inlet valves 28. The compressed mixture willpass from the port 10 into the outlet and collecting reservoir 11 fordistribution to' the system. Unless special means were provided in thisoutlet, any liquid with the refrigerant would be carried into the systemas rapidly as it passed into the outlet chamber. To preclude such anoperation, and to efl'ectivelv maintain a desired condition of liquidwithm the system and within the compressor, there is provided a specialform of separator illustrated in Figs. 4 and 5. This comprises a'tube 63threaded into the cylinder 9 and projecting upwardly into the chamber11. Suitablv mounted within the tube 63 is a spiral 64 which may beconveniently formed of comparatively thin sheet material twisted to thedesired pitch. By reason of this construction, the mixture undercompression leaving the port 10 will be whirled violentlv with theresult that the liquid will be thrown outwardly by centrifugal actionand will collect in the reservoir 11,

the gas tending to pass upwardly to the outlet valve 65. This valvecomprises a cover plate 66,adapted to be secured above the reservoir,and has depending therefrom a bracket 67 carrying a baffle 68, thebafiie being adapted, with the parts in position, to overlie the outletfrom the tube 63. This causes the gas to be deflected downwardly in thegeneral direction indicated bv the arrows in Fig. 4 whereby it againtends to pick up a certain quantity of the liquid and carry the liquidso entrained into the port 69 and thence past the control needle 70 tothe outlet 71 leading to the condenser, as will be apparent to thoseskilled in the art. Since the compressor operates at a constant speedand serves to produce at all times a given degree of compression on thematerial handled thereby, the gas leaving the tube 63 and sweepingacross the surface of the liquid will tend to limit and control themaximum liquid level in the chamber 11 at all times. If the svstemcontains the required amount of liquid, the control will obviouslv besuch as to maintain a substantially constant liquid level in the chamber11, the maximum level being controlled by bafl'le 68. and the minimum bythe quantity in the system, which minimum can be regulated by theinitial charge. This liquid is permitted to flow back into the compressor through a port 72 thereby tending at all times to keep thepiston completely sealed and also to maintain the stuifing box chamber49 filled with liquid which enters through the ports 48. The pressure ofthe refrigerant is at all times effective on the surface of the liquidin the chamber 11 for forcing the liquid back into the compressor andmaintaining the desired lubricating and sealing conditions. While alarge number of different liquids might be utilized if desired, Ipreferably employ glvcerine since it not only has lubricating propertiesreferred to but is also effective for lowering the freezing point of anywater present thereby tending to prevent freezing of the valves and alsoserve, in the event a valve should become frozen, to assist in thawingit out.

While I have heretofore referred to the use of material such asgenelite, it will be apparent that other materials mav be used ifdesired.

I have hereinbefore referred to the use of glycerine as the lubricatingand sealing material. While glycerine may be utilized alone for thispurpose, I have found that glycerine alone when cool is extremely thickand viscons and enormously increases the friction load. With a H. P.motor of the lifting brush type, for example, it has been found thatwith pure glycerine the motor will draw as much as 1,000 watts ofcurrent and when using straight glycerine of a particularly anhydrousquality which has been permitted to drop to a low temperature, thebrushes at times would not lift at all. By utilizing with the glycerinewhich is a tri-hydric alcohol, a mixture of ethylene glycol, verydesirable results are obtained. Ethylene glycol is one of a large familyof glycols 0r di-hydric alcohols,

the family of glycols lying midway between alcohols as we ordinarilyknow them and trihydric alcohols or glycerine. It has been found thatthe glycols, and particularly ethylene glycol, produces with tri-hydricalcohols, and particularly glycerine, a mixture of comparatively lowviscosity, moderate density and fair lubricating properties. Theglycerine alone, as referred to, is objectionable under conditions ofextremely low temperature by reason of the high viscosity. By combiningthe glycerine and glycol in different proportions, mixtures having verydecidedly different characteristics may be obtained. With a mixture ofalmost pure glycerine the watt load remains extremely high for a periodof nearly an hour which is the time required to effect a substantialchange in temperature. For example, a mixture of 98% glycerine underordinary conditions will require in excess of 400 watts at starting, thewatt load dropping to approximately 260 watts after about 60 minutes ofrunning. A mixture containing 79% glycerine and 21% glycol under thesame conditions requires about the same watt load in starting. This loadin about three minutes, however, drops to approximately 300 watts and inless than 10 minutes drops to a normal load of between 240 and 260watts, thereafter retaining substantially these characteristics.Expressing the characteristics of these mixtures in terms of actualtemperatures,it has been found that a98% glycerine mixture at 60 F. willrequire an expenditure in excess of 420 watts, the watt load graduallydropping as the temperature increases, but not reaching a stablecondition until a temperature of approximately 130 is reached. A mixtureof 79% glycerine and 21% glycol on the other hand, at a temperature of45 F. will require a watt load of about 420 watts, this dropping to 320watts at about 54; to 26570 watts at 70 F. and reaching a condition ofconstancy of about 250 watts at 95 F. As the percentage of glycolincreases, the rapidity of drop in watt load is quite marked, but thedesired lubrieating properties are not obtained. It has been found,however, that irrespective of variations in the mixture within certainlimits, after a normal maximum operating temperature of about 140 F. isreached, all the mixtures thin out to about the same viscosity andrequire about the same amount of power to overcome the friction load.

In view of the characteristics referred to, I have preferably utilized asealing and lubricating mixture comprising a tri-hydric and a di-hydricalcohol, preferably glycerine and etylene glycol with less .than 98%glycerine and more than 2% of glycol, with the glycerine preferablyalways in excess of the glycol in very substantial quantities.

Certain advantages of the present invention arise from the provision ofa compressor automatically lubricated and sealed in combination withmeans limiting the amount of sealing liquid which can be circulatedthrough the system by the compressor.

Other advantages of the invention arise from the use of a compressorincluding a stufling boX and piston, both of which are liquid sealedunder such conditions that the pressure set up by the compressor iseffective for forcing the sealing liquid into sealing and lubricatingposition.

Still other advantages of the invention arise from the use of acompressor sealed with glycerine in a refrigerating system whereby thefreezing point of any water therein is lowered, and the freezing ofvalves is obviated.

Still other advantages arise from the provision of improved means forseparating the compressed refrigerant and liquid and for maintaining apredetermined head of liquid available for sealing and lubricatingpurposes.

I claim:

1. A compressor, comprising a cylinder having inlet and outlet valvesfor each end thereof, a double acting iston in said cylinder, operating.means or said piston, a separator cooperating with said outlet valvesand including deflecting means operative under normal conditions ofoperation of the compressor for exerting a restraining influence on anundesirable increase in the liquid level in the separator, and means foreffecting a liquid return from said separator to said cylinder at apoint intermediate the ends of said piston.

2. A compressor, comprising a cylinder having inlet and outlet valves, apiston in said cylinder, operating means for said piston, .a separatorcooperating with said outlet valve and including deflecting meansoperative under normal conditions of operation of the compressor forexerting arestraining influence on an undesirable increase in the li uidlever in the separator, and means for e ecting a liquid return from saidseparator to said cylinder.

3. A compressor, comprising a cylinder having an inletand an outletvalve, a piston in said cylinder, operating means for said piston, anoutlet reservoir into which said outlet valve discharges, means withinsaid reservoir operative under normal conditions of operation of thecompressor for tending to limit the maximum liquid level therein, saidreservoir having a return connection to said cylinder, and an outletconnection from said reservoir above said means.

4. A'compressor, comprising a. cylinder having an inlet and an outletvalve, 2. piston in said cylinder, operating means for said piston, anoutlet reservoir into which said outlet valve discharges, means withinsaid reservoir operative under normal conditions of operation of thecompressor for tending to limit the maximum liquid level therein, saidreservoir having a return .connection to said cylinder, said meanscomprising a separator for effecting separation of the liquid and gasdischarged by said compressor, and an outlet connection from saidreservoir above said means.

5. In a compressor, a cylinder, a piston therein, an operating shaft forsaid piston, a stufling box for said operating shaft havin both endsthereof in free communication wit the interior of said cylinder, andmeans for liquid sealing and lubricating both said piston and saidstufling box.

6. In a compressor, a cylinder, a piston therein, an operating shaft forsaid piston, a stuffing box for said operating shaft havin both endsthereof in free communication with the interior of said cylinder, andmeans for supplying liquid to and liquid sealing said stufling box.

7. In a compressor, a cylinder, a piston therein, an operating shaft forsaid piston, a stufling box for said operating shaft having both endsthereof in free communication with the interior of said cylinder, andmeans for liquid sealing both said piston and said stufling box, saidmeans including a liquid separator and means tending at all times duringnormal compressor operation to limit the maximum head of liquidforsealing purposes.

8. In a refrigerating system, refrigerant circulating connectionsincluding valves, compressing mechanism for the refrigerant, and bafllemeans controlling the amount of liquid circulated through said system,and having a tendency during normal compressor operation to limit thelevel of the lubricant supply.

9. In a refrigerating system, refrigerant circulating connectionsincluding valves,compressing mechanism for the refrigerant, and meanscontrolling the amount of liquid circulated through said system, saidmeans comprising a separator and baflle having a tendency during normalcompressor operation toward limiting the maximum head of liquid in saidseparator.

10. A compressor, comprising a cylinder having longitudinally extendingintake and outlet passages in one of the walls thereof in adjacentparallel relationship, heads for said cylinder having ports cooperatingwith said passages and provided with inlet and outlet valves, an inletconnection communicating with one of said heads, and a separatorcooperating with an intermediate portion of said outlet passage andcommunicating directly with the inside of said cylinder to maintain abody of sealing fluid therein.

11. In a compressor, a cylinder, a double acting piston therein, anoperating shaft for said piston, and gas and liquid separating meanshaving a tendency during normal compressor operation toward limiting themaximum head of liquid seal on both the piston and shaft.

12. A compressor, comprising a cylinder having longitudinally extendingintake and outlet passages in the walls thereof, heads for said cylinderhaving ports cooperating with said passages and provided with inlet andoutlet valves, an inlet connection with said compressor and a separatorcooperating with said outlet passage and communicating directly with theinside of said cylinder to maintain a body of sealing fluid therein.

13. A compressor, comprising a cylinder having inlet and outlet valvesfor each end thereof, a double acting piston in said cylinder, operatingmeans for said piston, a separator cooperating with said outlet valves,said separator including a bafile effectively tending during normalcompressor operation to limit the maximum liquid level in the separator,and means for effecting a liquid return from said separator to saidcylinder.

14. In a compressor, a cylinder,a piston therein, an operating shaft forsaid piston lying in the plane of said piston with its axissubstantially intersecting the axis of the piston, bearing for saidshaft, a stuffing box for said operating shaft exteriorly of one of saidbearings and in free communication with the interior of the cylinder,and means for liquid sealing and lubricating both said piston and saidstufling box.

15. In a compressor, a cylinder, a piston therein, an operating shaftfor said piston lying substantially in the plane of said piston andhaving its axis substantially intersecting the axis of said piston,bearings for said shaft, a stufling box for said operating shaftexteriorly of one of said bearings and in free communication with theinterior of said cylinder, and means for supplying liquid to saidstuffing box and liquid sealing the same.

16. In a compressor, a cylinder, a piston therein, an operating shaftfor said piston lying substantially in the plane of said piston andhaving its axis substantially intersecting the axis of said piston, astufling box for said operating shaft in free communication with theinterior of said cylinder, and means for liquid sealing both said pistonand said stufling box, said means including a liquid in said separatorand means having an eflective tendency during normal compressoroperation toward limiting the maximum head of liquid in said separatorfor sealing purposes.

17. In a compressor, a cylinder, a piston, inlet and outlet connectionsfor said cylinder, a reservoir in communication with said outletconnections, and a separator in said reservoir, there being deflectingmeans cooperating with said separator effectively tending during normalcompressor operation to limit the maximum fluid content therein.

18. In a compressor, a cylinder, a piston therein, an operating shaftfor said piston having an enclosed bearing at one end through which theshaft does not extend, an intermediate bearing adjacent the opposite endthrough which the shaft does extend. there being a passage from saidcylinder to the side of the last mentioned bearing remote from thecylinder, a chamber into which said passage leads, and a stufiing box insaid chamber having both ends in free communication with said chamber.

19. In a compressor, a cylinder, a piston therein, an operating shaftfor said piston having an enclosed bearing at one end through which theshaft does not extend, an intermediate bearing adjacent the opposite endthrough which the shaft does extend. there being a passage from saidcylinder to the side of the last mentioned bearing remote from thecylinder, a chamber into which said passage leads, and a stufling box insaid ehamber having both ends in free communication with said chamber,said stuffing box being carried by and rotatable with said shaft.

20. In a compressor, a cylinder, a piston therein, an operatin shaft forsaid piston having an enclose bearing at one end through which the shaftdoes not extend, an intermediate bearing adjacent the opposite endthrough which the shaft does extend, there being a passage from saidcylinder to the side of the last mentioned bearing remote from thecylinder, a chamber into which said passage leads, and a stuffing box insaid chamber having both ends in free communication with said chamber,said stuffing box being secured to said shaft adjacent said lastmentioned bearing for rotation with the shaft.

21. In a compressor, a cylinder :1 piston therein, an operating shaftfor said piston having an enclosed bearing at one end through which theshaft does not extend, an

having an enclosed bearing at one end through which the shaft does notextend, an intermediate bearing adjacent the opposite end through whichthe shaft does extend, there being a passage from said cylinder to theside of the last mentioned bearing remote from the cylinder, a chamberinto which said passage leads, a stuffing box in said chamthrough whichthe shaft does not extend, an-

intermediate bearing adjacent the opposite end through which the shaftdoes extend, there being a passage from said cylinder to the side of thelast mentioned bearing remote from the cylinder, a chamber into whichsaid passage leads, a stuffing box in said chamber having both ends infree communication with said chamber, said stufiing box being carried byand rotatable with said shaft, and means for liquid sealing andlubricating both said piston and said stuffing box.

24. In a compressor, a cylinder, a piston therein, an operating shaftfor said piston having an enclosed bearing at one end through which theshaftidoes not extend, an intermediate bearing adjacent the opposite endthrough which the shaft does extend, I

there being a passage from said cylinder to the side of the lastmentioned bearing remote from the cylinder, a chamber into which saidpassage leads, a stufling box in said chamber having both ends in freecommunicationwith said chamber, said stuffin box being secured to saidshaft adjacent said last mentioned bearing for rotation with the shaft,and means for liquid sealing and lubricating both said piston and saidstufiing box.

25. In a compressor, acylinder, a piston therein, an operating shaft forsaid piston having an enclosed bearing at one end through which theshaft does not extend, an intermediate bearing adjacent the opposite endthrough which the shaft does extend, there being a passage from saidcylinder to the side of the last mentioned bearing remote from thecylinder, a chamber into which said passage leads, a stuffing box insaid chamber having both ends in free communication with said chamber,said shaft being of reduced diameter Within said chamber exteriorly ofsaid bearing and having the stuffing box mounted on the portion ofreduced diameter, and means for liquid sealing and lubricating both saidpiston and said stuffing box.

26. A compressor, comprising a cylinder having inlet and outlet valvesfor each end thereof, a double acting piston in said cylinder, operatingmeans for said piston, a separator co-operating with said outlet valvesand including a deflecting means disposed centrally with respect to saidseparator and having down-turned edges formed thereon and having aneflective tendency during normal compressor operation toward limitingthe maximum liquid level in the separator, and means for effecting aliquid return from said separator to said cylinder at a pointintermediate the ends of said piston.

27. A compressor, comprising a cylinder having inlet and outlet valves,a piston in said cylinder, operating means for said piston, a separatorcooperating with said outlet valve and including a deflecting meanscentrally disposed within the separator and having downturned edges andhaving an effective tendency during normal compressor operation towardlimiting the maximum liquid level in the separator, and means foreffecting a liquid return from said separator to said cylinder.

28. A compressor, comprising a cylinder, having an inlet and an outletvalve, a piston in said cylinder, operating means for said piston, anoutlet reservoir into which said outlet valve discharges, means in saidreservoir having an effective tendency during normal compressoroperation toward continuously controlling the maximum liquid leveltherein, said means including a centrally disposed bafile havingdownturned edges spaced from the walls of said reservoir, a returnconnection from said reservoir to said cylinder, and an outletconnection from said reservoir above said bafile.

29. In a compressor including a cylinder having removable heads eachcarrying an inlet and an outlet valve together with inlet and outletpassages formed therein, there being longitudinally extending passagesformed in the cylinder wall and communicating ing therewith, a piston insaid cylinder, operating means for said piston, a separator carried bysaid cylinder and communicating at one end with one of thelongitudinally extending passages, and a return connection from saidseparator to said cylinder.

30. In a compressor including a cylinder having removable heads eachcarrying an inlet and an outlet valve together with inlet and outletpassages formed therein, there being longitudinally extending passagesformed in the cylinder wall and communicating therewith, a piston insaid cylinder, operating means for said piston, a separator carried bysaid cylinder and communicating atone end with one of the longitudinallyextending passages, and a return connection from said separator to saidcylinder, said separator including a centrally dis osed baffle havingdownturned edges provi ing a liquid pickup space therebelow.

31. In a compressor including a cylinderhaving removable heads eachcarrying an inlet and an outlet valve together with inlet and outletpassages formed therein, there being longitudinally extending passagesformed in the cylinder wall and communicat- 5 ing therewith, a piston insaid cylinder, op-

erating means for said piston, a separator carried by said cylinder andcommunicating at one end with one of the longitudinally extendingpassages, and a return connection 10 from said separator to saidcylinder, said separator including a centrally disposed bafile havingdownturned edges providing a liquid pick-up space therebelow, therebeing an outlet connection from said separator 15 above said baflle.

In testimony whereof I have hereunto set my hand.

FRANCIS A. VVEGENER.

inlet and an outlet valve together with inlet and outlet passages formedtherein, there being longitudinally extending passages formed in thecylinder wall and communicat- 6 ing therewith, a piston in saidcylinder, op-

erating means for said piston, a separator carried by said cylinder andcommunicating at one end with one of the longitudinally extendingpassages, and a return connection 10 from said separator to saidcylinder, said separator including a centrally disposed baflie havingdownturned edges providing a liquid pick-up space therebelow, therebeing an outlet connection from said separator above said bailie.

In testimony whereof I have hereunto set my hand.

FRANCIS A. VVEGENER.

GERTIFICATE 0F CORRECTION.

Patent No. 1,912,926. June 6, 193a.

FRANCIS A. WEGENER.

It is hereby certified that error appears in the printed specificationof the above numbered patent requiring correction as follows: Page 6,line 61, claim 16, strike out the words "in said"; and that the saidLetters Patent should be read with this correction therein that the samemay conform to the record ot the case in the Patent Office. Sign d andsealed this 22nd day of August, A. D. 1933.

M. J. Moore.

(Seal) Acting Commissioner of Patents.

CERTIFICATE OF CORRECTION.

Patent No. 1,912,926. June 6, I933.

FRANCIS A. WEGENER.

It is hereby certified that error appears in the printed specificationof the above numbered patent requiring correction as follows: Page 6,line 61, claim 16, strike out the words "in said"; and that the saidLetters Patent should be read with this correction therein that the samemay conform to the record of the case in the Patent Office.

Signed and sealed this 22nd day of August, A. D. 1933.

M. J. Moore.

(Seal) Acting Commissioner of Patents.

